2 FTP Client

2.1 Introduction

Ftp client processes exist only when you use them. When you open a ftp connection a client process will be spawned and added as a dynamic child to the ftp supervisor in the inets supervision tree. When you close the connection the client process will be terminated. Only the process that created the ftp-connection will be permitted to use it, and if that process dies the connection process will terminate.

The client supports ipv6 as long as the underlying mechanisms also do so.

2.2 Using the FTP Client API

The following is a simple example of an ftp session, where the user guest with password password logs on to the remote host erlang.org, and where the file appl.erl is transferred from the remote to the local host. When the session is opened, the current directory at the remote host is /home/guest, and /home/fred at the local host. Before transferring the file, the current local directory is changed to /home/eproj/examples, and the remote directory is set to /home/guest/appl/examples.

      1> application:start(inets).
      ok
      2> {ok, Pid} = ftp:open("erlang.org").
      {ok,<0.22.0>}
      3> ftp:user(Pid, "guest", "password").
      ok
      4> ftp:pwd(Pid).
      {ok, "/home/guest"}
      5> ftp:cd(Pid, "appl/examples").
      ok
      6> ftp:lpwd(Pid).
      {ok, "/home/fred"}.
      7> ftp:lcd(Pid, "/home/eproj/examples").
      ok
      8> ftp:recv(Pid, "appl.erl").
      ok
      9> ftp:close(Pid).
      ok